Savage bell is the same pitch, 1/8 scale, M1 I think is what it's called.
I run a savage flywheel/bell/clutch on mine, but I had to move the trans forward about 1/4". I slotted the holes for the trans, cut a bit out of the brake area with a dremel, got everything lined up and installed, then drilled 2 holes through the chassis/trans flange so I could key the trans to the chassis with a nut and bolt. I didn't trust the 4 trans screws keeping it from moving around.
I run the same when I use a small block as well. Just had to get a crank extender so the 1/8th clutch setup would fit on a SB length crank.
Traxxas clutches never lasted long for me. I used one for about a month (1/2 gallon) and the slipping drove me nuts, so I did what I did. With a decent BB, it's pretty much a necessity to run 1/8 clutch setup or it just slips all the time... I ran an XTM24.7 and OS21RG in mine with teflon/carbon shoes and it did fine. As soon as my LRP28S3 was broken in, the clutch slipped a lot still, so I got 1/8th hard alloy shoes. Now it does really well.