Well I finally went and got some 72 pin connectors from Newark, the non-zero-insertion-force kind. Here's what I was planning on doing with a throwaway NES toaster deck once I find one for dirt cheap.

Take a perf board and string some wires in the back for the contacts, get the contacts aligned so the cart can be inserted in the top one label up while the bottom connector is placed on the motherboard.

So, I'll most likely disable the springboard that lets the cart drop down or remove it and instead make a guide rail that will direct the cart straight into the connector. Only thing I'm wondering about is how much reinforcement I'll need for the setup and how hard it will be to insert/remove carts after this is done. Those connectors seem pretty tight.

This should make a nice cheap alternative to a top loader if it pans out, and I won't have to hack up the original casing either. I really wish the guy who made the NESp would put pictures up of his custom top loader he claims to have made on his website.