Firstly, Welcome.
That is a real nice example of an original factory 78E Standard. Should have a lot of fun on it, your bike and if you want to Hardtail it, it is your money and bike.
Only 2 things...........Edit: 3 (Clutch Master cylinder),................... i see that are not factory original. First the mufflers, Second is the seat-cover. 2 models in 78 and the cover is for a 78 but for the Special model 78SE, not the Standard 78E.
An original 78E in Star Black Tins
View attachment 274011
Any problems at all, Ask. Do not buy anything before Asking first.
Made this up to help identify the different models, it also includes information and tip bits, (Post #7) that relate to these older bikes. A seat from Texivana will help with your height. Lowering the bike front and back will help as well, but a caution, lowering the front to much, can cause the guard to hit the bottom of the triple. small increments with a flatter seat should help,
https://www.xs650.com/threads/xs650...workshop-manuals-and-other-information.30569/