Hi, I've got a '67 Coupe, practically same car, same engine bay and I've got a Weiand Stealth highrise 8020 with a Demon Jr. (same as holley), a 1/2" phenolic spacer and a drop base 14" air cleaner with 3" filter and still clear my turn signal hood. I think the last time I measure it was ~1/2"-1" of clearance with all that added. The drop base air cleaner is the key. I can measure with out the air cleaner to see what the clearance is from the top of the carb base but it'll be at the end of the week, traveling for work.
You could put some clay on top to see exactly, I just layed a telescoping pencil magnet next to the carb, closed the hood then measured how far it stuck up above the air cleaner.
Someone does make adjustable motor mounts, not cheap ~$200 I believe, check summit. You can use solid but I hope you don't have any fillings, and be sure you still use a rubber trans. mount or you'll crack the bellhousing I've read. Solid mounts are for racing, not fun on the street. Lakewood makes a good stiffer than rubber mount I've read, summit sells too.
You could always make a torque strap for the front of the motor if you want, that way you could take it off if you don't like it.
Jon