Hello

Well I been working on this 65 merc for some time now and finally got it painted. Now previously I installed a 302 and kept the three speed in place of a I-6. I really like this engine but it is due for a rebuild and I have other options. I have a 1977 F-250 2 wheel drive sitting in my yard with a C-6 and 460. I really would like that engine combo and it would be an easy swap considering I have a parts truck. However fuel economy is a concern along with price. I have approximately 3000 to spend on a build. I think I could get alot more engine for 3000$ compared to the 302. The 460 runs fine just has a leaking rear main seal. So fuel economy, power and price my three considerations. What would you do. Im steering strongly towards the 460 but I live 45 mins outta town so i need to get decent economy. Also with my 28 spline rear end would it hold up to the 460?