Post #8.
Photo 1. 1967 Spa Francorchamps, #21 - Lotus 49 of Jim Clark, #32 - Cooper T81 of Guy Ligier.
Photo 2. You've had it already, signed as 1965 Spa, which it really is. The car in the front is #7 BRM P261 (Graham Hill), #17 - Lotus 33 (Jim Clark), #8 - Jackie Stewart in another BRM P261, #10 - Richie Ginther's Honda RA272, #1 - John Surtees in a Ferrari 158, #21 - Jo Siffert's RRC Walker Brabham BT11, then possibly Dan Gurney in a #15 Brabham BT11, Cooper T77 of Jochen Rindt and Honda RA 272 of Ronnie Bucknum.
Photo 3. Some IndyCars, as was already said.
Photo 4. Juan Manuel Fangio in a Ferrari 801 at 1957 Monaco GP, methinks.
Photo 5. IndyCar, too.
Photo 6. I'd say it's a 1968 Spa Francorchamps, Brabham BT26, Jochen Rindt.