Seat Belts

Bunch O questions-
1. No seat belts in the back- Plan to ride the girls (4 and 6) around back there in booster seats, Lots of choices, leaning toward the 3 point non-retractables, but not sure how to mount them.
Anybody done this? Ideas on the best mounting point for the shoulder strap bolts?
(LIMEY- pay attention, you'll need to know this soon enough)

2-swapping out the bench for swivels, will need to change the belts. Want the three point retractable bucket type up there to replace the current 3 point retractable bench belts-Can anybody recommend a brand? Googled and came up with several companies that had the metal buckles very similar to the GM original push buttons. Can't tell if the retractor will fit in the original position, and i don't want to chop anything up.

I checked around for used GM belts, found a few, but don't want to risk the younguns on 35-40 year old belts and retractors.

Hey cap I am good on belts brother switching to bench seat in the El Camino they were NOS included with Limey so all good there brother

Juiced-

When you say the fronts didn't fit the stock location, do you mean where the retractor bolts in?

I ride my 3, 5, & 6 year olds in the back of mine with just the lap belts & boosters. The 6 year old doesn't use a booster since he's legally old enough not to need one, but regardless it seems to work better than the 3 points that newer cars have. I just don't like the way 3 points come up on kids' faces or you just end up tucking them behind the seat anyways. On the 3 year old's full booster, there is a loop that is specifically made just for lap belts & it feels VERY secure when you tighten it up.

Call me old fashioned...... call me crazy...... but I think lap belts properly secured to the base of a full harness booster is more than adequate. I do agree to get new belts though, if for nothing else than safety. You wouldn't bungee jump with a 15 year old strap, you wouldn't skydive with a 20 year old parachute, why would you trust your children's safety with 30+ year old seat belts? OK, that's enough of my rambling for now.

You are right about the booster, IF it has the shoulder straps in the seat- My boosters are just the little seats that raise them up high enough for the lap belts to be effective and to get them up where the vehicles shoulder belt crosses their shoulder. If I hit something head-on with just the lap belts back there(EEK) they would bend in half like a slinky, nothing to restrain their upper bodies. Don't want their little faces to smack the back of the fronts seats. The boosters I have are very effective if the car is equipped with back seat three pointers-they work great (and as recommended by NHTSA and the manufacturer) in my Explorer.
My wife has the full child restraint seats in her 4runner, they are about to outgrow them anyway. I'm just thinking that the 3 point non-retractable can be tightened manually and would hold them securely as they grow.