New 700R won't go into 1st

[75sierraclassic]

Hey I swapped an '87 700R-4 in my 75 GMC Sierra Classic. It replaced a stock turbo 350. As you know the 700 has an extra gear to it. The problem is, my steering column does not have enough range to manually shift my tranny down to 1st gear. It will go into 2nd and that is it. I am wondering if there is an internal stop in the column that I can modify. I was also thinking about modifying the shifter linkage arms to different lengths to get more travel. Have any of you guys tackled this problem.
I appreciate any help.
Thanks