Hello, my Spyder is a GS SM5, so base model with a clutch. There are a few options:
Motorcycle Foot Pegs, 360° Rotating Adjustable Front Rider Footpegs &
Motorcycle Front Rider Footrest Adjustable Extend Foot Pegs Rotatable.
I chose the former because they are cylindrical and knurled all the way around; similar to a dirt bike. The latter is more of a board than peg; similar to Harley's, fork mounted, or engine guard mounted. You are correct, certain models have different pegs. However, I'd say about 75% of aftermarket WILL fit; with some or quite a bit of alteration/modification. I chose a brand that was too short so I added shims. If you chose a brand that is too long; that would fall into the 25%. Don't get too confused with all the options. The only difference is fronts have a return spring and the backs usually have a hole with a ball and spring so they stay up when you fold them; similar to the top of a closet door. Just pay attention to the distance from the hole and where the peg meet the bracket, that will tell you everything. If you fall in love with a certain style and want to put that on both, that's when you will be doing some modifications. I didn't like the "OH Sh_t" handles so I removed the bracket underneath the seat that housed them, lowered my seat height 1.5 inches, and am in the process of installing the same grips I have on the handlebars on the back. Sound cool? Most sane people have said I'm nuts for going through all that grief for being picky about sissy bars. I say it depends on the level of discontent for said sissy bars or the level of grief! Long story short, when it comes to this stuff, don't be too picky. When I get to the house I can send you some pics of the pegs, clutch and brake lever, grips, and my American Flag tire valve caps. I removed all the fenders so you can see what they look like with out them. Oh that reminds me, what color is your Spyder? I told you my Spyder was a base model, but the original owner spent over $2,200 trying to convert it to a Touring Model, so I have Corbin Fleetside Saddle Bags and Passenger Back Rest with storage taking up space in my garage. They are painted "body color red." Ash