Thanks Ryk. Honestly I haven't even got to looking into doing this quite yet, but the shim blocks / longer bolts and fab on the shift rod sound like the most feasible option. I did a search of old forum posts about this and learned that wildmike had done a similar mod. So I sent him a PM to pick his brain on the "how too" also.
I'm thinking of perhaps fabricating a new brake & shifter brackets (& linkages) to accomodate clearing in front of the pipes....and welding on new mounting points on the front side of the frame tubes might be the cleanest way to go about it.
