4 answers
Thanks @Anup Jadhav for you help.We can not modify the Permissions Set if these are the part of package.But we can Insert new Permissions Set by Using Post Install Script.I have Implemented this and my Permissions Set includes:App permissionApex Page & Apex ClassObjects & Field Permissions and may more.If someone needs any help on Permissions Set ( of Standard Objects when these are the part of Package and having Master-Detail relationships with our Custom Objects), Please feel free to post your Comments on this post.Thanks,Kapil Kaushik