New Diffs coming, couple ??

[JtkBrew]

Used V3 Kraton

Have seen a bunch of videos on differential service. I really wanted to change the fluid in all 3, but was a bit nervous to open up my diffs as I've never done it and was also concerned with what I'd find. I've read the V4 diffs are shimmed at the factory. I've looked on Jenny's and they have been out of stock. However, I saw this morning they were on Amazon. I went ahead and purchased the following:

2x https://www.amazon.com/gp/aw/d/B07SPF6L4Y?ref=ppx_pt2_mob_b_prod_image
And
https://www.amazon.com/gp/aw/d/B07SNGCZ5F?ref=ppx_pt2_mob_b_prod_image
And
https://www.amazon.com/gp/aw/d/B00SNCVII0?ref=ppx_pt2_mob_b_prod_image

I went this route because the differential gear kits cost more than the diffs I bought.

The plan:
Get the new diffs, replace the bearings on them with the Fast Eddy bearings, and change the fluid in them, probably to something like F20-C200R-50 (may go slightly higher in the center, but I don't want a total wheelie machine either). Once those are all set up and ready to install, I'll pull out my old diffs and install these. Then, at my leisure, I'll take the old ones apart and see whats going on inside. If it's not toast, I'll probably set the center one up with 500k fluid so I can see the difference. If the front & rears are ok, I'll service them and have a backup.

The questions:
I'm assuming I'll have to take these new diffs completely apart to change the bearings. Before I do that, what am I looking for slop wise to see if additional shims are needed?

Will the factory bearings come out pretty easily in a new diff, or are there tips for getting them out? Any tips I need to be aware of when changing the rest of the bearings on the truck?

I have a soldering station and MIP hex bits. I understand I'll most likely need heat to get the 5 screws that hold the motor/diff mount out to break the lock tight. Any other areas I need to be aware of that heat may be needed?

Anything else this greenhorn is not thinking about that I need to?

 

[SrC]

Bearings will come out easily. Running 200k center now (6S Kraton). I like it. Big diff over Stock. I have 500K here too to try. Running 20K/F and 60K/R. I might swap the F and R diffs to see the difference. Most 1/8 Track Truggies run Lighter CST in the rear. (looser rear). I just want to see the difference. Dissassembly the first time can be a bear. Once you do the 3 diffs, you can do it in your sleep. Watch some vids on maintenance and shimming. And don't over think the shimming part until you reinstall the rebuilt diffs. Just have enough shims on hand. Outboard bearing shims and inner spider gear shims at the very least. You said you got 3 new V4 diffs. Just examine how they are shimmed and follow suit.

 

[JtkBrew]

Bearings will come out easily. Running 200k center now (6S Kraton). I like it. Big diff over Stock. I have 500K here too to try. Running 20K/F and 60K/R. I might swap the F and R diffs to see the difference. Most 1/8 Track Truggies run Lighter CST in the rear. (looser rear). I just want to see the difference. Dissassembly the first time can be a bear. Once you do the 3 diffs, you can do it in your sleep. Watch some vids on maintenance and shimming. And don't over think the shimming part until you reinstall the rebuilt diffs. Just have enough shims on hand. Outboard bearing shims and inner spider gear shims at the very least. You said you got 3 new V4 diffs. Just examine how they are shimmed and follow suit.

Thanks @SrC. I've seen most people on here running thinner in the front on the Kraton, which is why I have that plan in my head. I'm really excited to get this upgrade done and get this thing out to see the difference. On the other hand I know we're in the heart of winter, so now is the time to have patience with it.