The main difference between 2-wheelers and the Spyder is the in steering input. Your 50 years of experience will both help and hurt you at first. You've developed a significant amount of steering memory in those arms. The brain says "turn right" & it happens. The arms already know what to do without having to think about every little act to get it done.
2-wheelers require a technique known as counter-steering, which involve inputs into the steering opposite the desired direction. You push forward on the right handlebar (in effect, turning the handlebars left) to initiate a right hand lean & entering into a right hand turn. Whether you've realized it or not, you've been using counter-steering for 50 years. Your arms know how to do it with you having to consciously think about how to do it.
The Spyder requires a direct steering input method: Steer right to turn right. I found I had to consciously think about how to make the turn on the Spyder because of all my years on the Goldwing. This is the case also while steering straight. You are constantly making small steering changes to stay in the center of the lane (BRP's recommended lane position, by the way). You might find this difficult at first because those arms are constantly wanting to steer you in the opposite direct you want to go. You'll have to reteach them new techniques to overcome so many years of muscle memory.
One more thing...
Timing on when to enter the turns is different than on 2-wheelers. The counter-steering technique requires you to begin the turn steering inputs before you actually want to start the turn. You steer left, which initiates a right hand lean and then a right hand turn. There's a slight delay between the the time of the initial steering input and before the turn actually start. Again, this is something you likely haven't thought about for years, but it happens. It's something your arms already know. If you use the same timing on the Spyder, you'll find you are entering the turn a little too soon and will have to make a course correction to make the corner correctly. Just be aware that when you enter steering inputs that is when the Spyder begins the steering change. You may have to consciously think about when to turn.
I hope this is helpful. When I realized why I was having difficulties, correcting it was much easier & riding more enjoyable. I still have the Goldwing and I have found that switching between the two is easy.
Mark