Bicycle Mechanics - Help on Le Tour

I have a vintage 70's 10-speed Schwinn Le Tour that needs some repairs. First I need a new bottom bracket, what size?(this Le Tour was made at the Chicage plant). Second, the chain guard is rubbing the rear deraileur due to some bends; should I replace it or can I just permanently take it off(I have seen some other Le Tours with no chain guards).Lastly, any hints on replacing the BB?
Thanks

Yup, if the BBs not been removed since the 70's, you may wish to start dribbling some penetrating fluid such as plusgas onto the threads now as it may be fairly tight or seized. Plusgas is good if you can let it soak in for a day or two. Good luck :).

Why do you think you need a new BB? Chances are you can take the one you have apart, clean and repack it and be good.

If you need a new BB, then you will need to take the old one apart and measure the width of the spindle (not including any threads) as well as the distance between the cones and the length of each shaft end. From these measurements, you *might* be able to find a replacement. If you need new cups, you will need to get the right threading for your BB shell. Be aware that the drive side cup is probably reverse threaded.

Getting the BB apart and reinstalling it requires a crank puller, a spanner wrench for the left side lockring, and a pin spanner to hold the left side cup for tightening and adjusting. If you need to remove the drive side cup, you will need a big wrench or special tool to fit the flats on the cup. If you just need to repack the bearings, you do not need to remove the drive side cup.

The chain guard is rubbing the rear deraileur due to some bends; should I replace it or can I just permanently take it off(I have seen some other Le Tours with no chain guards).Lastly, any hints on replacing the BB?
Thanks

I have a very smiliar bike that had the same problem. Since removing the chain guard can cause problems with pinching (Did it on my Huffy, now can't get the blasted thing back on because I lost the screws...big screwup that) I'd suggest simply bending it back into shape. I use my omnipotent crescent wrench for that, but I"m sure any sturdy lever with a slot that the metal fits into will do the trick.

I definitely need a new bottom bracket since the one I have broke off between the crank arm and the spindle, However I do not have the tools to replace the BB, should I have it replaced at my LBS? About how much will this cost?