First of all it depends on ur category. If ur from general category and if u want gud branch in Mtech its impossible in IITs. I have secured 60.21 marks in GATE 2016 and im dng my Mtech in NIT SURAT. I have not got any specialization in top NITs also. All the best for ur future. Its better to check the cutoffs in Inspire and Ignite.com

It would be difficult to get old IITs.

Please check the cutoff marks used for the past years to get an idea. Check here. The cutoffs will vary for the M.Tech course and IIT. Most of the cutoffs are also given as GATE scores so ple check the article and then apply accordingly.