Hey that's real dirt! Lookin good Dave!
On that speedo problem, the speedo sending unit on the front axle is easily destroyed if it's not mounted right. There is a metal driving dog in there that fits into the soft plastic notches inside the speedo unit. You have to rotate the pieces with your finger to line them up to fit into each other before you tighten down the axle. If you don't line up the dogs right, the whole deal will still bolt together OK, but then the plastic part self destructs in short order. Not sayin that this is what happened, but it fits the facts.
Here's a pic of the sending unit and you can see the plastic piece inside there--
A new one costs about $65. But, (silver lining) if your Stroker wheel was giving you an inaccurate speedo reading, you can buy a new front unit with a different ratio to correct the error. You'd have to ask some GS guru to find out which one to get.