I have the some of the specs for the CVO-253 cam but they are at the house, had to beg to get what I got..... I know the lift is .530", which is .022" (point gap for a Panhead)more then the SE-211. Difference is all in the timing, remember the CVO-253 is EPA legal and it is the cam in all the SE 103" bikes and the 103" kits.
As for who suggested the cam change, that would be me. I pulled the front head to see how big a cam could be installed without doing anything else. The problem is clearance for the valve seal, min spec is .080", would have been down to .026" with the SE-251 on the front exhaust. I've used the SE-211 before in a 103" with 9.8 to 1 compression, awesome bottom end right where you ride 98% of the time!
I'm guessing here: a .030" Cometic gasket would bump compression 1/4 to 1/2 point? One would have to cc the heads to kown the correct answer. I'm thinking any increase would be a plus. In my opinion the SE-251 would be the logical choice once all the valve clearances were set, the SE-257 likes compression and raising the compression is a liitle more difficult in this motor then a normal TC-88 because of the hemi combustion chamber.
Final question; I used the stock pushrods because I had both rocker boxes off and the base circle from the CVO-253 to the SE-211 is only .020" difference. I'll throw a set of adjustables at it if BEAR complains about valve train noise when hot.
The weather here has been rain and more rain, so he hasn't been able to put any miles on it, he has a nice surprice waiting for him.