700r4 shifts hard & late

[1adam12]

i have a 70 the PO had a 700r4 put in he had a chessy bracket for the tv cable so I bought the kit from bowtie overdrives installed the new spring and it still shift hard..but it now goes in overdrive. But the first 2 shifts are around 2,500-2,700rpm..am I doing something wrong or is there something wrong with the tranny? I have researched and I have the tvset up as per BTO instructions..but I did not use a pressure gauge ..thanks