Multiple questions

1. Wondering if anyone has any information on this transaxle axle ?

2. Has anyone tried this with a pillow block in hopes it will help with having less stress on transaxle or if people think it will work or stay away from the idea also putting new needle bearing in the transaxle and its already welded

3. Debating on going with 18.5 opposed briggs or 20 intek v twin briggs for the build. Will be a trail rig but also want to play in some mud and go 40mph if even possible. Kinda trying to hit all areas witch I'm not sure if it's even possible to have that happy medium

4. exhaust on both motors  what are people's opinions. True duals 2 into single exhaust? H pipe or x pipe and then one pipe each side? Plan on having a muffler either way want to still sound good and aggressive but not super loud since I am tossing around the idea of doing cut outs also

Sorry about the split text. I'm trying to figure it out. I'm on my phone and could nit find the green pencil to hit enter

I'll let someone with more transaxle experience than I help there but as for exhaust... 2 into 1 will work better in the low to mid range and 2 seperate will work better in the higher rpm ranges so for trails and mud I'd suggest going with a 2 into 1 as it will provide a better all around powerband.  I'm not sure if a X or H crossover would make enough difference on a small engine to be worthwhile, maybe/maybe not?

To make a 2 into 1 perform the best it can without 10 pages of math, keep these things in mind:
- Size matters! That doesn't mean bigger is better though, try to match the size of your pipe as close to the size of your exhaust ports as possible to keep flow velocity up.
- Equal length header tubes that merge into a collector that is about 1-1/2 times bigger than a single header tube will aid exhaust scavenging and keep flow velocity up.

There's more I could go on about but it'll get boring! Lol.

As for editing, when you're logged in look at one of your posts in the top right corner for this.

Yeah, outer supports seem to help those that have them.  As for needle bearings.  If it has them and they ain't broke or worn, don't bother changing.  If you want to change Brass to needle.  Go for it!  I saw someone did that somewhere, but it has been several years as to where I saw it.