if its a re ring...then ur stuck with the regular 225 rods,pistons.
I'd mill the block .036 before it go's together and then the head .024, then do some 318 valves, not the 1.70/1.44..but if those r all u can get or make work, then fine.
Since u know a lil about porting,, ill tell u this...DO NOT RAISE THE ROOF MUCH.lol...u'll hit water on the low side of the guide as well..lol...the floor/bowl/ssr is where u find the most cfm gain....funny ports they are. 'ill be experimenting some more with them to get ready for an up coming job'
I would also 'done this at home' cross drill the crank for full time oiling and at the same time keep the standard main bearing and surface so that it all stays together and even runs a lil cooler. only has 4 mains and an 85 lb crank flying around..lol..btw u have to go through the convertor pilot register to get that last main to rod drilled through.
You can also make or buy a windage tray, weld a baffle into the sump with vents for drain back.
The super 6 intake is nice...nice and heavy.lol...but the header add on will lighten it a lil at the same time. I like the long tube heads...i used the MP one for my 71 swinger...but u need the early style.
Also the head gasket 'between 3/4 near the intake side can be opened up to the water passage, this helps the those cylinders cool better 'they tend to run hotter for obvious reasons'
as for cams?
yeah the ones offered sound crummy.lol...but these dont like to rev without a lot of compression and cam...and well, they dont do well 'being a smaller cid' with power under the bigger cams curve.
I ran the old MP .460/268* cam....but i think they need more lift...like .490-.520 lift and the same 268*-272* duration 'faster lobes'....hate to say it but maybe talk to hughes or engle about it.