Could someone tell me what is involved in converting from manual to power brakes in a 68 Chevelle. Whould it be worth the trouble? Thanks

Do it! As soon as you can! There's no question that it's worth it!

I converted my '72 Malibu to power brakes, no sweat. Went to a junkyard, found a power master cylinder that fit, took it out of the car it was in.

Removed my manual master cylinder, put the power one in (it's at an angle, attaches to the lower hole on the pedal), got a bench bleed kit from NAPA, bench bled the MC right on the car, no problems there. My hard lines had some spirals in them at the master cylinder, so it was no problem stretching them up to meet the (now angled) master cylinder. Found a plug in the intake manifold (right behind the carb)for the vacuum fitting (luckily I had pulled that out of the donor car's manifold), bought about a foot of big vacuum line and some hose clamps, hooked the manifold vacuum port to the master cylinder, bled the brakes.

http://www.nonseq8r.com/chevy/DCP_0028.JPG
You can see in the picture the vacuum line that goes from the MC to behind the carb, and the stretched out spirals in the hard lines.

The brakes work better than they ever did. I used to get nervous about the manual drums, but now that I've got power, I'm sorry I didn't do it sooner. It was very easy, and DEFINITELY worth it. Do it as soon as you can. graemlins/thumbsup.gif

One word of warning: If you buy the MC from a junkyard, there's no way to know if it works well enough to stop a car. TEST THE BRAKES WELL in a safe environment before driving around.