Hi nezugic,
Welcome to the Heartland Owners Forum. Heartland was formed about 10 years ago and purchased the rights to the Prowler name a few years ago. So a 1986 build pre-dates that by quite a bit. It's possible that someone on the forum may have had some experience with Prowlers back then and might know the answer.
We do have an extensive collection of manufacturer manuals here, but most are more recent. They may be of help to you to some extent.
Here's a link.