Tranny Trouble and annoyance

[91gst]

Well about 1000 miles ago I installed an ACT 2600lb clutch and Fidanza Flywheel in my first gen GST. I have been having some trouble putting the car into first second and reverse ever since. Even when I am stopped I have tried to put it through every gear and they all seem like they are being forced in but sometimes it won't go in gear without me pressing the clutch a couple times and then putting it in and its still hard. Also when I go into reverse I shift into second then reverse which seems to work sometimes but when it doesn't it'll grind. One other problem that I have encountered is when I put it in first the car will start to move forward. Does anyone have any suggestions on what I should try to fix these problems? Also would getting my tranny rebuilt help? Right now the car only has 56,xxx miles. Also if getting the tranny rebuilt would help how much should I expect to pay? Sorry for the long post. Thank You

[FourG63 97GST]

I know what you are talking about, Ive having the same problem with my tranny, but its a tranny I bought used that its happening to.
the car drove fine on the previous tranny after i installed the clutch, so it has nothing to with the clutch(for me). The tranny been sitting for awhile so I hoping its need to be broken in abit.
its hard to get it in first w/o forcing it, I have to put in second gear then put it in first. and it grinds trying to put it in reverse

when I find the problem Ill let you know