Glad to hear you got it together. Here is how I've modified a couple Hustler motor mounts to provide belt adjustment. It is just 1 1/2 angle welded to the stock mount with slots cut in it. On the 980 you will wither have to open up the hole in the body for the duct to be able to slide back, or unbolt the duct from the engine and attach it to the body so that the engine will slide independently of it... you will need to trim either the engine shroud, or the duct a bit to do this.
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