I have two Speedway tanks. The red one came off my 1971 Shrike. The Orange one came off what I thought was also a 1971, but now I'm not sure. Note that while both tanks join either side of the frame with nuts and bolts, the red one joins my 1971 with a single tab at the back, which bolts into the top of the frame. The orange one, however, has no tab, but instead joins the frame at the back with two nuts/bolts on either side of the frame. Problem is, the orange one is sooooo much cleaner than the red one. I'd like to use it on my 1971, but I'd also like my bike to be correct. Any thoughts on this?