SBC-700R4 in 71-drill cross member?

[Steve Van Gent]

Guys,

Just dropped in 350 and 700R4 in sons 71 truck (origional 250-6 and 3 speed manual). Used mounts and cross from doner long bed truck 72 over to his short step side (it had stock 350/th350 eng/trans). I have moved the power steering box, column, shift links, etc from doner truck. The engine perches are in the forward set of holes, we were very careful to copy the stock install from the 72 doner truck. Now we are trying to bolt up the cross member and holes do not line up...

Here are a few questions;

1. Is the 700R4 longer to tail than the th350? Is it normal to have to re-drill holes for cross-member? Do I need all 8 bolts, or just 4 lower OK?
2. We used chop saw to remove the bell housing cross member from frame, kind of ugly, but rivits dont seem to want to come out-appears hot-rivits. Is there a better way to remove?
3. lengthing drive shaft to exactly 59"...does this length seem correct for application? Typically lengthen?
4. COlumn shift appears to be correct and dry-shifts fine. DOesn't this mean length is correct?
5. Any other 'gotcha's' I should watch for?

Thanks,

Steve