Planning on replacing motor monts on brothers 69
and was wondering what the best way to do this. I have heard of people just jacking the motor up a few inches, is this possible its a small block by the way, would you need to unbolt tranny cross member.?

You should be able to weasel 'em out by jacking up the engine a bit. NOT on the front damper/balancer!

I've used a small hydraulic "bottle" jack up against the oil pan rail (with a hunk of 1x1 wood) with good results. Keep an eye on distributor / accessory clearance.

The tranny mount should have enough flex in it to do the job.