The factory started out thinking something about 1500 would be a good run, but demand far-outstripped that #. They increased production and the # considered to have been built for model year 1985 is 8,800. If the steering head stickie is on there still, and the info isn't worn off, the month and year should be printed.
Let's say Sept to June is the 'season' for production, with July and August being set aside for new tooling. Assume an equal # of production each month, for 10 months. 8800 motorcycles/10 months = 880 motorcucles/month. Yours is 1787 1787/880 = 2.03, so the beginning of the third month of production. If production begins in Sept. that means your bike was built in the third month, November. Now if the beginning month is different, say, June, and 10 months of production ending in March, you would adjust for that. In short, your bike was manufactured in the third month of production, using this method. You could claim it's an "early bike," and you'd likely be correct. Does that make it worth more than a last month of production motorcycle, Not to me! However, condition is much more important than month of manufacture, unless you happen to have the #1 bike in production, or the final bike (the latter being harder to prove, as records for end of production are likely unknown) an operable motorcycle with no mechanical issues is a better value than an inoperable one.
The 1985 models are the only year to have embossed side plates with VMax. All other years have stick-on plastic emblems. Footpegs are different on the '85's, the VBoost is different (smaller dia.), and the exhaust is different. Others may chime-in on other differences for the 1985 model year.
Pinstriping is a skill which looks easy,but is infuriatingly hard to do well. You want some interesting history of hot rodding and pinstriping, look-up 'Ken Howard,' and be prepared to spend some time reading.
Ken Howard was possibly mentally-ill, and definitely a substance abuse victim. His poison of choice was alcohol. He was well-known in southern CA hot rodding circles, and Bud Ekins, who operated a shop, let Ken Howard occupy someplace at the shop. Howard had an old bus. In return, he would do the pinstriping on customers' bikes, cars, trucks, toolboxes, whatever. Ken Howard was also a skilled gunsmith.
Here's a Ken Howard story I've posted before. A guy brought his car to have Ken pinstripe it. The way he worked, you left whatever it was to be striped, and how much you were willing to pay. No, "this is what I want... ." Pay your shekels, and wait for the call to come get it.
The guy got the call, he showed up, and as he looked at the exterior, he didn't see any pinstriping. He got inside, and back then, cars had steel dashboards. At first glance he didn't see anything. Then he noticed something by the radio in the dash. He looked closer, and he saw musical notes, descending down from the radio, to the center of the bottom of the metal dashboard, where cars used to have an ashtray, you pull it out, some flipped open. He pulled out the ashtray, and Ken Howard had painted an orchestra inside the ashtray.
