Ed,
I agree with what others have said--the '65 set is fun to put together, and the high numbers are far easier than '66, '67, or '64. When I put my raw set together, I was lucky enough to stumble on to a local card shop that had just purchased complete high-number runs of '64 and '65 Topps (multiples of each). I wasn't able to be picky about centering, but I got nice fresh copies of almost all of the cards in one feel swoop.
The cards that took me a lot longer were the low and mid numbered Yankee cards, especially the Richardson (second to last card I picked up).
Richie Allen, Bill White, Tony C., Denny McLain, Giants Rookies w/ Murakami, Tony Oliva, Rocky Colavito, Curt Flood, Elston Howard, Yogi Berra, Tug McGraw, and Al Downing were also fairly tough.
Good luck with your set!!!!!