I have the BBK 1 5/8 chrome longtubes on my '85. They've been on for a couple of years now and still look good, although I have to admit that I polish 'em whenever I do the rest of the car.
I had the trans and bell housing out when I put them on, so I just stuck 'em in from the bottom. You will have to jack the motor up to put 'em on, but that's no big deal. I've done it on a couple of other cars. I would recomend the BBK's, as I picked up a couple of tenths with them over the JBA shorties I had on the car before.