Sprocket Adapters

[Keith]

So, now that we have gathered up all the parts to replace the undercarriage on my Dad's old 420C, I have had a different thought about how to install the 350 sprockets. Normally this would involve putting a new rim on the 420, but that just sounds way too easy, and being one to never take the easy path, I was thinking of going ahead and machining up some adapters to make this a bolt on job. I have plenty of big steel and a lathe big enough to turn them. my thought is to make a set that will bolt onto the 420 axles, then bolt the 350 sprockets onto the adapters. We are not going for a restoration look (it is going to end up with 350 tracks and idlers anyway), more of a "resto-mod" as they say in the muscle car world. Has anyone ever tried this before?

Now the second one, I am considering trying to get the track frames off my donor 440 to fit on the old 420. Totally differnet mounting, but I am wondering if a custome set of cross bars or brackets might do the job. Those hydraulic track adjusters sure would be nice.....

Getting back to reality, just in case my ambitions have exceeded my free time, does anyone know if replacement recoil springs are available for the 420, or do I need to look for used ones?

Thanks,

Keith