I am running into the same dilemma with my L83 Chev engine install scheduled for this weekend. Need to replace the original heater hoses first but require longer hoses with a close right angle near the firewall connection. But removal of the manifold will allow access same as yours. Robbie from Motech even said to cut some of the strength ribs off the back of the last intake runner to make more room. My engine is direct injected so manifold removal is pretty simple. Much like taking a cylinder head off a flathead Ford V8 - 10 minutes (if you drink beer).