For almost all applications we offer sub frame connectors for we do not offer bolt-in sub frame connectors (SFCs). If the attachment points do not offer a solid and purpose built bolt mounting area and would require drilling holes through the sheet metal unibody then we only offer weld in SFCs for these applications.
In a short amount of time these drilled holes will just oblong and defeat the entire purpose of installing SFCs. For these applications weld in SFCs are the only "right" way for installation.
For applications that we may offer bolt on SFCs we feel the bolt mounting locations (normally existing factory mounts) are adequate to properly mount the SFCs.