ur help please in 2009 shelby gt500

hello every one hope are of u are fine.

i am new here. i want to buy a 2009 shelby gt500

mods: jlt CAI, flow masters cut back, pullyes, sct dyno tune 551 whp 12psi

the problem is the gear or transmission issue i drove the car its very nice. but changing gears where ok after a while it became hard between 1st and 2nd

it has a mecload clutch and a fly wheel. is this common in shelby 2009> i was driving down the road (testing) gear in 3rd. clutch 1st time i didn't pull out 2nd time it did quickly but i felt that the gear stick wanted to stay in 3rd.

is changing the clutch to SPEC stage 3 will solve this issue

i really like the car but im still thinking is this normal.. i stopped the purchasing for now. because of that. is there any solution for this issue?

please i need all of your help and advices. is it just a clutch issue? or its normal and i can use it.. when 1st driving it there is nothing wrong smooth in 1st and 2nd but after pressing on gas and stopping then in 1st again its 2 to 3 time to get in.

is 12 psi safe?

or agency is very bad here in servicing and this car came from America to the middle east. and there prices is too high. getting the transmission down is only like 830 dollers

thank you and regards, sorry for the poor english